The mailshell looks good so far. Between midnight last night and 9:00 am this morning, it caught 87 spams, missed 7 and 1 false positive. Not bad to start. It learns so it should do better with time. Tomas, thanks for the tip!

You are welcome, credit is due to one of Pocomail users whose name unfortunatelly slipped out of my memory, who had similar need and compared several products and reported back with mailshell.
I didn't know about that before, and it's actually well hidden on their website, as it seems they are mostly targetting corporate customers.